You owe your little hands, do you often use your hands to hurt your scalp?
(Source: soogif)
When you scratch your scalp, do you often pick out some small particles?
Looking at the small particles with blood scabs and herpes in the crevices of your fingers, will your little head be full of question marks?
(Source: soogif)
There are two possible cases.
1. Relatively healthy
Appearance: White or pale yellow, small in size, the size of a millet.
Cause: Too much oil from the scalp accumulates in the ducts of the pilosebaceous glands. If it is not discharged in time, it will gradually concentrate and become granular “whiteheads”.
(source: drawn by myself)
Other parts of your body produce a lot of oil, especially your face, chest, and back, or “oily skin”[1].
A lot of oil, which means your male hormone secretion is a bit strong. You are either a 30-60 year old tough guy or a pre-menopausal girl[1], am I right?
2. Relatively unhealthy
Appearance: Large particles, even flakes, as large as snowflakes; scalp itching, dandruff, etc.
Cause: The high probability is folliculitis; in severe cases, scalp hair follicles and abscesses [2].
These particles are the blood scabs, pus plugs, and a mixture of bacteria and fungi that grow after the abscess ruptures.
Folliculitis may be caused by some bacteria, but it is more likely a fungus called “Malassezia”, also known as “Pityrosporum” [2-4]. It accounts for 96% of all scalp fungi [5].
(Malassezia under scanning electron microscope [1]. Source: Lasers Surg . Med)
Malassezia loves oils, and the scalp is their “cafeteria”[5].
It is also an opportunistic pathogen [5]. As the name suggests, Malassezia is usually peaceful with us, and it will only cause disease under certain conditions.
For example, there is too much oil secretion, or the immune system is low, or the hair is not washed all the time [3].
At this time, Malassezia can eat and grow vigorously, thus forming folliculitis.
But don’t be too nervous, it’s not that as long as the small particles can be pulled out, it is infected by the fungus.
Fungal infection is more likely if it is accompanied by an itchy scalp, rash, pustules, discharge, etc.
To confirm, you need to go to the hospital for a fungal test.
Malassezia breeds too vigorously, and its descendants take root in the hair follicles of the scalp, which will destroy the protective layer of the scalp – keratinocytes.
Destroyed keratinocytes slough off, resulting in dandruff.
(source: drawn by myself)
If inflammation is not controlled in time, the scalp will continue to be damaged and the stratum corneum will be significantly thinner.
People with dandruff have an average of less than 10 layers of scalp cells, while healthy people have 25 to 35 layers of scalp cells. Apparently, the defensive barrier of the scalp is severely weakened [7,8].
(source: drawn by myself)
Malassezia “pulls” some “volatile organic compounds (VOCs)” in the process of “gluttonous” hair oil. In large quantities, it emits a unpleasant smell[9].
What’s more scary is hair loss! In the alopecia population, the proportion of Malassezia infection was significantly higher [10].
Malassezia thrives in the hair follicle and breaks down the oil in the hair follicle into free fatty acids. Free fatty acids repeatedly stimulate the hair follicle, eventually causing the follicle to expand and rupture, releasing its contents into the surrounding tissue to produce an inflammatory response. Hair follicles will also be destroyed one by one, resulting in hair loss!
(source: drawn by myself)
Although hair loss is related to many factors, such as heredity, age, sex hormone levels, hair nutrient intake, mental state, etc. [11], the scalp “species” is out of control and the “ecosystem” is destroyed , or will let the hair ruthlessly abandon you.
Hair follicles also contain hair follicle stem cells responsible for regeneration, and if they are also attacked, they are replaced by scars, resulting in “scarring alopecia”. This hair loss is irreversible, that is, permanent hair loss [12].
1. Eat less spicy and spicy food and don’t drink alcohol[13-15].
2. Don’t scratch your head.
3. Pay attention to rest, do not stay up late.
4. Wash your hair frequently and choose a shampoo that inhibits fungus, such as ketoconazole lotion.
5. Change the pillowcase 1~2 times a week.
If the condition is serious, with rashes or pustules all over the head, pus, exudate, itching and pain in the scalp, affecting work or even sleeping, don’t hesitate, hurry up Go to a dermatologist!
Image source: Zhanku Hailuo
What other hair and scalp health problems do you have
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Contributing Author: Gong Long |M.D., Chinese Academy of Medical Sciences and Peking Union Medical College
References
[1]Ro BI, Dawson TL. The role of sebaceous gland activity and scalp microfloral metabolism in the etiology of seborrheic dermatitis and dandruff[J]. J Investig Dermatol Symp Proc, 2005,10 (3):194-197.
[2]Lei Wanjun, Dai Tao. Dermatology [M]. People’s Military Medical Press, 2011.
[3]Malassezia species in healthy skin and in dermatological conditions. Prohic A, Jovovic Sadikovic T, Krupalija-Fazlic M, Kuskunovic-Vlahovljak S. Int J Dermatol. 2016 May;55(5):494-504.
[4]Malassezia ecology, pathophysiology, and treatment. Theelen B, Cafarchia C, Gaitanis G, Bassukas ID, Boekhout T, Dawson TL Jr. Med Mycol. 2018 Apr 1;56(suppl_1 ):S10-S25.
[5]CW Saunders, A. Scheynius, J. Heitman, Malassezia fungi are specialized to live on skin and associated with dandruff, eczema, and other skin diseases, PLoS Pathog., Volume 8, Issue 6, Page e1002701, 2012, doi: 10.1371/journal.ppat.1002701.
[6]JW Lee, BJ Kim and MN Kim, Photodynamic therapy: new treatment for recalcitrant Malassezia folliculitis, Lasers Surg. Med., Vol. 42, Issue 2, pp. 192C196, 2 January 2010, doi: 10.1002/lsm.20857.
[7]Lu Yonghong, Ran Yuping. Malassezia and dandruff[J]. Journal of Dermatology and Venereology, 2001, 008(004):267-268,263.
[8]Kerr K, Darcy T, Henry J, Mizoguchi H, Schwartz JR, Morrall S, Filloon T, Wimalasena R, Fadayel G, Mills KJ. Epidermal changes associated with symptomatic resolution of dandruff: biomarkers of scalp health. Int J Dermatol. 2011 Jan;50(1):102-13.
[9]Gonzalez M, Celis AM, Guevara-Suarez MI, Molina J, Carazzone C. Yeast Smell Like What They Eat: Analysis of Volatile Organic Compounds of Malassezia furfur in Growth Media Supplemented with Different Lipids.Molecules. 2019 Jan 24;24(3):419.
[10]Nematian J, Ravaghi M, Gholamrezanezhad A, Nematian E.Increased hair shedding may be associated with the presence of Pityrosporum ovale. Am J Clin Dermatol. 2006;7(4): 263-6.
[11]Al Aboud AM, Zito PM.Alopecia.2020 Sep 29. In: StatPearls [Internet].
[12] Qi Shiling, Zhao Ying, Zhang Xiaoting, et al. Analysis of clinical and pathological features of 53 cases of cicatricial alopecia [J]. Chinese Journal of Dermatology, 2013, 46(010) :731-735.
[13] Zhang Hong, Chao He’an, Wu Chipeng, et al. Epidemiological study on risk factors of seborrhea-related diseases in adolescents and their correlation with digestive tract diseases[J] . Chinese Journal of Dermatology, 2006, 39(2):102-104.
[14] Li Junfeng, Ma Junping, Liu Jie, et al. Keloid folliculitis in the neck [J]. Chinese Journal of Dermatology, 2011(11):60.
[15]Anonymous. Epidemiological study on diseases related to Malassezia infection in Changchun area[J]. Chinese Journal of Endemic Disease Control (No.5):492-493.
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